Some, though not all, of the ATW 150 fleet are arriving back from their exterior re-paint with the interiors having been given a refresh, including new seat covers, flooring, panelling and a deep clean. I wouldn't go so far as too call it a refurbishment and the choice as to which 150s are getting the interior refresh does seem to be completely random.

If the 2020 deadline wasn't looming I'd say that if all of the 150 fleet was getting the interior refresh and deep clean at the same time as the exterior re-paint that would be enough to see them through to electrification.
Unfortunately some of the 150s are arriving back from the re-paint still very tired and worn inside.

The 142s aren't being touched at all and again some of the 143s have been re-painted but all have been left untouched inside.